JOURNAL OF ROCK MECHANICS

JOURNAL OF ROCK MECHANICS

Investigating the stability of northern slope in the Zarshouran gold mine

Articles in Press

Document Type : Original Article

Authors
emad qaraqiye salimi 1
ehsan taheri 1
parviz moarefvand 2
1 Department of Rock Mechanics, Faculty of Engineering, Tarbiat Modares University, Tehran, Iran
2 Department of Rock Mechanics, Factuly of Mining Engineering, AmirKabir University of Technologh, Tehran, Iran
10.22034/irsrm.2026.579093.1076
Abstract
Slope stability in structurally complex open‑pit mines requires realistic representation of jointed rock mass behavior, particularly during the early stages of mining when geomechanical data are limited. This study investigates the stability of the northern slopes of the Zarshouran Gold Mine using three‑dimensional Discrete Element Method (DEM) modeling implemented in 3DEC. The geomechanical parameters were calibrated through an integrated approach combining the Geological Strength Index (GSI) and back‑analysis of observed slope behavior, providing a constrained and field‑consistent parameter set for numerical simulation. Under natural pre‑mining conditions, the slopes exhibit a high level of stability with an overall factor of safety (FoS) of approximately 8, while groundwater effects induce only negligible creep‑like displacements (≈ 1×10E(-7)m) along lithological contacts. Simulation of the final pit geometry indicates that progressive mining and partial removal of the limestone unit reduce the stabilizing overburden weight, decreasing the FoS to approximately 1.5. The model predicts a maximum shear strain rate of ~2×10E(-1) SE(-1) and a maximum block velocity of ~1.7 ×10E(-5) m⁄s, concentrated in the central slope region and aligned with structural weakness planes, indicating the initiation of progressive sliding.
The results highlight the importance of integrated parameter calibration and 3D DEM modeling for reliable stability assessment and long‑term geotechnical risk management in open‑pit mines.
Keywords
Slope stability
Open-pit mine
Distinct Element Method (DEM)
Numerical modeling
Subjects
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JOURNAL OF ROCK MECHANICS

Articles in Press, Accepted Manuscript
Available Online from 11 June 2026